This invention relates to the preparation of N-hydrocarbylcarbonyl-5-(1-hydrocarbylcarbonyloxy)hydrocarbylpyrrolidin-2- one and to a process for the preparation of the S-enantiomer of this compound.
The N-hydrocarbylcarbonyl-5-(1-hydrocarbylcarbonyloxy)hydrocarbylpyrrolidin-2- ones are useful as intermediates in the preparation of 5-(1,2-ethylenically unsaturated hydrocarbyl)pyrrolidin-2-ones. The 5-(1,2-ethylenically unsaturated hydrocarbyl)pyrrolidin-2-ones are useful in the preparation of 4-amino-5-alkenoic acids which are known to have biological activity. In particular, 4-amino-5-alkenoic acids are known as irreversible inhibitors of .gamma.-aminobutyric acid transaminose rendering the compounds useful in the treatment of disorders of the central nervous system function. It is the S-enantiomer of such compounds which show such activity.
The present processes for the preparation of 5-(1,2-ethylenically unsaturated hydrocarbyl)pyrrolidin-2-ones and the 4-amino-5-alkenoic acids involve complicated synthesis schemes and expensive reagents.
What is needed is a process in which the optical activity of the intermediates useful in the preparation of 5-(1,2-ethylenically unsaturated hydrocarbyl)pyrrolidin-2-one and 4-amino-5-alkenoic acids is retained. What is further needed is a process for the preparation of intermediates useful in the preparation of such compounds which uses relatively inexpensive reagents and involves relatively straightforward synthesis schemes.